A Review On: Nature’s Bio Sensors - Plants

Abstract

Plant leaves help with air pollution by absorbing pollutants through both their surface and their tiny pores (stomata) and by participating in photosynthesis, which removes carbon dioxide and releases oxygen. Plants are exposed to various harmful air pollutants, which cause oxidative stress and pose a threat to plant health, agriculture production, and vitality of ecosystems. Despite the climate actions and technological development, most ecosystems and agricultural areas are exposed to high levels of tropospheric ozone, nitrogen oxides, and particulate matters (PMs). To use plant trees to investigate the air pollution. Leaf surfaces were heavily loaded by dust particles but the stomata were not occluded, the cuticle was thinner, other anatomical properties were unaffected.

Introduction

This study investigates urban air pollution by comparing particulate deposition and basic chemical indicators on leaves collected from sites with different pollution levels, such as busy roads, residential areas, parks, and industrial zones. Since motor vehicles are a major source of urban air pollution, leaves of common tree species (neem and mango) were used as natural bioindicators to assess pollution exposure.

Using simple and low-cost methods, leaf surface dust was washed and quantified, pH of leaf extracts was measured, and chlorophyll content was assessed through color analysis. Samples were collected from polluted areas (Pimple Saudagar and Bhosari) and less-polluted areas (PCCOE Campus and Ravet). Results showed that leaves from high-traffic and polluted sites accumulated significantly more particulate matter, had lower (more acidic) pH values, and displayed reduced chlorophyll content. In contrast, leaves from cleaner areas had less dust, near-neutral pH, and darker green coloration, indicating healthier photosynthetic activity.

Conclusion

Based on the comparison of leaves from 2 polluted and 2 less-polluted regions, the study clearly shows that air pollution has a measurable impact on plant leaves. 1) Higher particulate deposition was consistently found on leaves from polluted sites. 2) Leaf extracts from polluted areas showed lower pH, meaning greater exposure to acidic pollutants. 3) Chlorophyll content was reduced in polluted area leaves, indicating stress and lower photosynthetic activity. 4) Visible differences in leaf colour and dust deposition further support the laboratory findings.

References

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Copyright

Copyright © 2025 Falguni Bhavsar, Pallavi Ingle, Aditi Bhole, Variya Chugh. This is an open access article distributed under the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.